<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>发送 AJAX 请求</title>
</head>

<body>
    <script>
        // 发送 AJAX 请求, 返回的结果是 Promise 对象
        function sendAJAX(url) {
            return new Promise((resolve, reject) => {
                //1. 创建对象
                const x = new XMLHttpRequest();

                //2. 初始化
                x.open('GET', url);

                //3. 发送
                x.send();

                //4. 事件绑定
                x.onreadystatechange = function () {
                    if (x.readyState === 4) {
                        if (x.status >= 200 && x.status < 300) {
                            //成功啦
                            resolve(x.response);
                        }else{
                            //如果失败
                            reject(x.status);
                        }
                    }
                }
            })
        }
    
        //promise then 方法测试
        // sendAJAX("https://api.apiopen.top/getJoke").then(value=>{
        //     console.log(value);
        // }, reason=>{})
  
        // async 与 await 测试  axios
        async function main(){
            //发送 AJAX 请求
            let result = await sendAJAX("https://api.apiopen.top/getJoke");
            //再次测试
            let tianqi = await sendAJAX('https://www.tianqiapi.com/api/?version=v1&city=%E5%8C%97%E4%BA%AC&appid=23941491&appsecret=TXoD5e8P')

            console.log(tianqi);
        }

        main();
        
    </script>
</body>

</html>